As widely known, musk-type perfume has been praised as an expensive perfume from ancient time, and with not only the elegant and fascinating fragrance but also with the high fixating effect which prevents diffusion of other volatile perfume compounds, it has been widely used as perfume for fragrances. In recent years, accompanying with the progress of chemical technology, the component of natural musk was isolated and its structure was determined, and chemical synthesis thereof has become possible. On the other hand, many compounds having musk-like fragrances which are not present in nature such as nitro musks or polycyclic musks were discovered and have been widely used as substitutes for those originated from animals or plants. Recently, accompanied by the increasing attention to diversified needs of consumer and safety of chemical substances, an expectation to macrocyclic musks with high biodegradability is growing and various new macrocyclic musk-type perfume compounds have been developed one after another.
As to the macrocyclic musks, it has been known for many years that C14-C16 lactones generally have musk-like fragrance. However, the fragrances of those lactones considerably differ in quality and intensity, and those which are practically valuable and commercially available are few such that only 3 or 4 compounds are mentioned. For example, as most popularly used one, 15-pentadecanolide or 11- (or 12-) pentadecen-15-olide is mentioned. In addition, according to non-patent reference 1, 7-hexadecen-16-olide (paper 105) or 16-hexadecanolide (paper 923) are mentioned as valuable ones as substances of musk fragrance.
Moreover, in patent reference 1, processes for production of various C14-C17 lactones are described. In the patent reference 1, it is described that, in those lactones, the first or second position from cyclic oxygen may be substituted with a methyl group, or may have a double bond in the second or third position from the cyclic oxygen atom, and in those lactones, 15-methyl- and 14-methyl-pentadecanolide, etc., are also included. Those compounds were synthesized according to the production method of the above-mentioned 11- (or 12-) pentadecen-15-olide, but the patent reference 1 describes only that those compounds have an interesting fragrance, and does not indicate anything about a fragrance nature of the respective lactones.
And, in patent reference 2, it is described that many of saturated or unsaturated, unsubstituted or methyl substituted 14-17 cyclic members lactones are macrocyclic musk lactones. However, those lactones relate to a using method of ω-halogenated fatty acid which is a useful precursor thereof, and in the patent reference 2, no reference to the fragrance nature of the respective lactones is made.
And, in patent reference 3, too, it is described that 14-methyl-11-hexadecen-16-olide, 14-methyl-12-hexadecen-16-olide and 14-methyl-hexadecanolide are valuable perfume substances having strong and comfortable musk fragrances. However, the patent reference 3 only makes reference to the three compounds and it does not make any reference to similar species with different carbon number. According to the non-patent reference 2, as to the musk-like fragrance of the macrocyclic lactones, it is indicated that a strong musk-like fragrance is presented around the carbon number of 14 to 16, and it is also indicated that the musk-like fragrance is decreased in the macrocyclic lactone with carbon number 17, therefore, compounds of similar species with less carbon number are expected to have a stronger musk-like fragrance. Here, the production method of those compounds is, similar to the method of 11- (or 12-) pentadecen-15-olide, that in which cyclododecane is used as starting material.
Moreover, in patent reference 4, odorizing compositions containing various 15-17 cyclic member lactones are described. In the patent reference 4, it is described that, in those lactones, between the third position from cyclic oxygen atom and the fourth position from carbonyl group in general formula may be substituted with a methyl group, and may have a double bond between the third position from the cyclic oxygen atom and the third position from the carbonyl group. It is also describes that those compounds have a civet smell and often have a side note like a face powder, like a fruits and like a flowery odor. In the patent reference 4, it is described that several tens of compounds having the above-mentioned formula were actually obtained, together with their fragrance natures. According to that, the respective compounds have musk-like fragrances in common, but other than that, have side notes characteristic to them. That is, in perfume materials, change of fragrance nature based on a small structural difference is significant, and, as a result, it can be said that a value as a perfume material can be found only by actually preparing the compound and by smelling its fragrance.
As mentioned above, various studies have been made for the macrocyclic musks, but those actually being used in the perfume industry are only 3 or 4 compounds mentioned first. In order to respond to the diversified customer's needs, it is desired to develop novel macrocyclic musks having better fragrance characteristics.    Patent reference 1: JP-B-H54-8677    Patent reference 2: Specification of Canadian patent No. 1221105    Patent reference 3: JP-A-H10-204078    Patent reference 4: JP-A-H11-193395    Nonpatent reference 1: S. Arctander, Perfume and Flavour Chemicals    Nonpatent reference 2: Abe, Perfume Materials, 96, 19-27 (1970)